NRF52 PM_EVT_ERROR_UNEXPECTED problem with connection

[Mario]

hello,

I used nrf52 and softdevice 2.0.1 and i have a big problem.

For some times the BT works perfectly but after i connect more then 4 devices for some reason the device return PM_EVT_ERROR_UNEXPECTED end stop working. The reset do not help i used sd_nvic_SystemReset() and NVIC_SystemReset() even i trya power off the BT module, but this error still happens

i received this error(PM_EVT_ERROR_UNEXPECTED) every time when i want to connect to a BT module to a phone.

Any ideas what cause this.

[Petter Myhre]

It is reserved below the bootloader in flash. See this.Is your bootloader start address 0x77C00? I think you should set it to 0x77000 instead. Then you can leave DFU_APP_DATA_RESERVED to 0x1000, and the flash between 0x76000 and 0x77000 will be reserved for your data by the bootloader. It seems that Fstorage doesn't know know that you have in flash below 0x77000, so I think you should try to set FS_PAGE_END_ADDR manually. Try setting it to 0x76000, and see if that changes anything.

[Mario]

After we have changed the address as you suggested, I am not getting the error PM_EVT_ERROR_UNEXPECTED. But I observe strange behavior of the record mentioned above - the records are stored in pages starting (0x73000), (0x74000), (0x75000) - is that normal?

Since before I change the addresses the flash(bootladder first page) was corrupted(I suppose), should I expect similar problems after the addresses were changed, because of this strange use of the pages?

[Petter Myhre]

Good. Yes, that is normal. Unmodifed, the Flash Data Storage module will use three flash pages. 1 swap page and 2 two for data. I didn't quite understand your last question, please elaborate.

[Mario]

Thank you very much for your support!

I want the peer information for all phones being paired to the BT module to be preserved between DFU OTA updates and powering off the module. (On the next connection attempt by a phone which was paired before, no pairing/passkey request to be performed. I want the phones which were paired before the DFU/power off to connect without a pairing request as it was before the DFU/power off.)

How this could be achieved?

I added the (0x73000), 0x74000), (0x75000) to the DFU_APP_DATA_RESERVED, but this did not help - after the DFU/power off the phones which were paired before, now on the next connection attempt were requesting a pairing/passkey confirmation.

Please comment. Thank you in advance!

[Petter Myhre]

I need to look into how to keep bond information when doing DFU, but the bond information should still be there if you do a reset (power off->power on), are you saying that it is not?

[Mario]

The information is still there in the flash, but the phone still want a pairing request. (after DFU/power off)

Where the bond information is store? if it is stored in the FDS, why it is update every time when connect a phone?